"Essentially, marijuana can consume all the water. Every bit of it," said state Fish and Wildlife Senior Environmental Scientist Scott Bauer, who specializes in salmon recovery and is working on a study of the issue.

The findings, expected to be released soon, shed new light on a massive, largely unregulated industry in California that has been blamed for polluting streams and forests with pesticides and trash and for bulldozing trees and earth to make clearings for gardens.

"The destruction of habitat is actually quite staggering," said Patrick Foy, a spokesman with the state Department of Fish and Wildlife.

Last year, 24 North Coast salmon-bearing tributaries were reported to have gone dry, Bauer said, though not all were verified by the agency.

Even without drought, there isn't going to be enough water to meet the pot industry's growing demand, Bauer said.

Just the illegal marijuana plants confiscated in California by law enforcement in recent years — between 2 million and 4 million annually — use upward of 1.8 billion gallons — or about 600,000 water tanker trucks over their five-month growing season, based on the average water usage documented in the study.

That amount is enough to stanch the seasonal flow of many small creeks in the region, potentially stranding the young salmon and steelhead that decades of taxpayer-funded efforts have sought to restore.

"It's really an important issue for fish," Bauer said. "We've invested a lot of money in these salmon and steelhead stock."

The North Coast sits at the center of the escalating environmental crisis. Its remote forests and seemingly ample water supplies have long made the region famed territory for West Coast pot cultivation, earning three counties — Mendocino, Humboldt and Trinity — the much-trumpeted "Emerald Triangle" moniker.

That notoriety is now marked, however, by the signs of widespread environmental degradation, endangering the region's clear, free-running streams and the wildlife that depends on them.

"I think it's really important that this industry, which has brought so much wealth to our communities and the region, take responsibility for its impacts," said Scott Greacen, executive director of Friends of the Eel River.

The state study Bauer led examined three watersheds in Humboldt County and one in Mendocino County, all of them renowned for marijuana cultivation. They include two near Redway, one near Orick and one that includes Willits.

The Redwood Creek watershed near Orick drains into the ocean. The other three watersheds feed the Eel River.

Using satellite images, researchers determined that an average of 30,000 plants were growing in each of the four watersheds in 2012, an increase since 2009 of 75 percent to 100 percent, Bauer said.

"We were able to count every plant and measure every greenhouse," Bauer said. The pot gardens they found ranged in size from 10 plants to hundreds, he said.

The greenhouse-plant counts are estimates, based on the size of the structures.

Researchers estimate each plant consumes 6 gallons of water a day. At that rate, the plants were siphoning off 180,000 gallons of water per day in each watershed — altogether more than 160 Olympic-sized swimming pools over the average 150-day growing cycle for outdoor plants.

Some marijuana advocates have taken issue with the 6-gallon-per-plant estimate, saying daily water use is considerably less. But Tim Blake, founder of the North Coast's Emerald Cup cannabis competition, said mature, tree-sized plants need closer to 15 gallons a day.

Plants grown in inland Mendocino County, where it's hot in the summer, will use more water, while those in cooler regions can use less, Blake said. He estimates it takes 60,000 gallons to 75,000 gallons to raise 25 plants, the current limit for medicinal marijuana in Mendocino County.

Sheriff Tom Allman has estimated there are more than 1 million marijuana plants being illegally grown annually just in Mendocino County. That doesn't include medical marijuana gardens.

Water and wildlife officials don't base their investigations on whether the marijuana being grown is for medical purposes. Instead, they look at the violation of laws meant to protect natural resources, including forests, soil and streams.

"If the operator is not in compliance with environmental laws, then they're not legal. That's the way I look at it," said Stormer Feiler, an environmental scientist with the North Coast Regional Water Quality Control Board.

The new study escalates scrutiny of North Coast pot cultivation and is likely to inflame a debate that has raged for years among supporters and foes of marijuana farms. The issue has even split growers in the industry, which has an annual estimated value that varies widely, from $10 billion to over $120 billion.

Until now, few official statistics have been available to inform the water-use discussion about marijuana. That is unlike the attention on other land-intensive industries, including the North Coast's famed wine crop, where water use has been documented and watched for years.

But with logging activity on the decline across much of the region and a thriving black market for pot — plus state-sanctioned recreational marijuana sales in Washington and Colorado — the spread of cannabis cultivation is now seen by many environmentalists and government scientists as the greatest threat to forests and streams damaged by decades of heavy human use.

"There's no real question the marijuana industry is now the biggest single sector in terms of our concerns," said Greacen, Friends of the Eel River director.

He said regulating the industry and its water use would go a long way toward fixing the problem.

If growers collected all their water during the rainy season and stored it in permitted tanks or ponds — like many other farmers — marijuana's water consumption would not be such an issue, Greacen said.

Blake, the Emerald Cup founder, agreed. He said most locally based growers are conscientious, both about staying within plant limits and using their own springs or buying tanks of water. But there are others who buy, rent or trespass on water-short properties and then divert water illegally to grow their crops, he said. Law enforcement officials say such growers also tap into neighbors' springs and water tanks.

"It's the big commercial growers that are giving all the people who have been doing a good job up here a bad name," Blake said.

Dale Gieringer, state coordinator of the National Organization for the Reform of Marijuana Laws, a group that advocates for marijuana legalization, said growers are taking too much of the blame for the state's water woes.

"I don't think marijuana is responsible for most of the water problems in California," he said. But, if the marijuana plant counts cited in the study are correct, "that could have an impact" in those watersheds, he acknowledged.

Wildlife officials are quick to say that many local marijuana growers are following the rules.

But there are quite a few who don't.

Fish and Wildlife officials last year investigated 264 marijuana-growing operations in the state and helped remove 129 illegal dams being used to irrigate pot, said Capt. Nathaniel Arnold, who runs the department's statewide marijuana team.

Of those operations, about 70 were in Lake and Mendocino counties, he said.

Agency officials say they are limited in what they can accomplish because they are outnumbered by marijuana-growing offenders.

"We just don't have enough staff" to investigate every complaint, Feiler said.

The cases often take years to investigate and prosecute.

State regulators recently worked on three cases, each involving an unauthorized dam on one tributary to the Navarro River in Comptche, west of Ukiah.

Another case involves a Willits-area property rented to marijuana growers who used bulldozers to clear several acres of forest.

On Friday, the Oakland landowner, Joung Min Yi, reached a settlement with the state that requires him to pay $56,404 in penalties for state and federal water code violations.

He also is required to restore the land, work that has reportedly cost more than $80,000, Feiler said.

Most cases pursued by water regulators are resolved through civil fines rather than criminal charges, in part because it requires fewer resources, he said.

Marijuana growers aren't the only ones taking water without permission. Last year, a Mendocino County vineyard was fined $33,800 for diverting water from an unnamed creek into its irrigation reservoir.

Legislators have proposed stronger environmental protection measures in response to the problem. Pending state legislation would boost funding for water and wildlife investigations connected to illegal marijuana cultivation.

In Mendocino County, Sheriff Allman has initiated a water theft hotline and said cases are being being vigorously prosecuted. The District Attorney's Office does not have statistics available on water prosecutions, spokesman Mike Geniella said.

The Department of Fish and Wildlife has put together a team dedicated to dealing with marijuana, Foy said. Water and wildlife officials also are asking marijuana growers to learn and follow water regulations. The State Water Resources Control Board website has information about obtaining permits to collect and store water.

The permits and requirements apply to any site preparation work, "regardless of crop," the state website notes.

Still, regulators and environmentalists are concerned that the explosion of marijuana in the region, without greater controls, will ruin the landscape for everyone.

"Essentially, marijuana can consume all the water. Every bit of it," said state Fish and Wildlife Senior Environmental Scientist Scott Bauer, who specializes in salmon recovery and is working on a study of the issue.

The findings, expected to be released soon, shed new light on a massive, largely unregulated industry in California that has been blamed for polluting streams and forests with pesticides and trash and for bulldozing trees and earth to make clearings for gardens.

"The destruction of habitat is actually quite staggering," said Patrick Foy, a spokesman with the state Department of Fish and Wildlife.

Last year, 24 North Coast salmon-bearing tributaries were reported to have gone dry, Bauer said, though not all were verified by the agency.

Even without drought, there isn't going to be enough water to meet the pot industry's growing demand, Bauer said.

Just the illegal marijuana plants confiscated in California by law enforcement in recent years — between 2 million and 4 million annually — use upward of 1.8 billion gallons — or about 600,000 water tanker trucks over their five-month growing season, based on the average water usage documented in the study.

That amount is enough to stanch the seasonal flow of many small creeks in the region, potentially stranding the young salmon and steelhead that decades of taxpayer-funded efforts have sought to restore.

"It's really an important issue for fish," Bauer said. "We've invested a lot of money in these salmon and steelhead stock."

The North Coast sits at the center of the escalating environmental crisis. Its remote forests and seemingly ample water supplies have long made the region famed territory for West Coast pot cultivation, earning three counties — Mendocino, Humboldt and Trinity — the much-trumpeted "Emerald Triangle" moniker.

That notoriety is now marked, however, by the signs of widespread environmental degradation, endangering the region's clear, free-running streams and the wildlife that depends on them.

"I think it's really important that this industry, which has brought so much wealth to our communities and the region, take responsibility for its impacts," said Scott Greacen, executive director of Friends of the Eel River.

The state study Bauer led examined three watersheds in Humboldt County and one in Mendocino County, all of them renowned for marijuana cultivation. They include two near Redway, one near Orick and one that includes Willits.

The Redwood Creek watershed near Orick drains into the ocean. The other three watersheds feed the Eel River.

Using satellite images, researchers determined that an average of 30,000 plants were growing in each of the four watersheds in 2012, an increase since 2009 of 75 percent to 100 percent, Bauer said.

"We were able to count every plant and measure every greenhouse," Bauer said. The pot gardens they found ranged in size from 10 plants to hundreds, he said.

The greenhouse-plant counts are estimates, based on the size of the structures.

Researchers estimate each plant consumes 6 gallons of water a day. At that rate, the plants were siphoning off 180,000 gallons of water per day in each watershed — altogether more than 160 Olympic-sized swimming pools over the average 150-day growing cycle for outdoor plants.

"We're still fairly shocked," by the results, Bauer said.

Some marijuana advocates have taken issue with the 6-gallon-per-plant estimate, saying daily water use is considerably less. But Tim Blake, founder of the North Coast's Emerald Cup cannabis competition, said mature, tree-sized plants need closer to 15 gallons a day.

Plants grown in inland Mendocino County, where it's hot in the summer, will use more water, while those in cooler regions can use less, Blake said. He estimates it takes 60,000 gallons to 75,000 gallons to raise 25 plants, the current limit for medicinal marijuana in Mendocino County.

Sheriff Tom Allman has estimated there are more than 1 million marijuana plants being illegally grown annually just in Mendocino County. That doesn't include medical marijuana gardens.

Water and wildlife officials don't base their investigations on whether the marijuana being grown is for medical purposes. Instead, they look at the violation of laws meant to protect natural resources, including forests, soil and streams.

"If the operator is not in compliance with environmental laws, then they're not legal. That's the way I look at it," said Stormer Feiler, an environmental scientist with the North Coast Regional Water Quality Control Board.

The new study escalates scrutiny of North Coast pot cultivation and is likely to inflame a debate that has raged for years among supporters and foes of marijuana farms. The issue has even split growers in the industry, which has an annual estimated value that varies widely, from $10 billion to over $120 billion.

Until now, few official statistics have been available to inform the water-use discussion about marijuana. That is unlike the attention on other land-intensive industries, including the North Coast's famed wine crop, where water use has been documented and watched for years.

But with logging activity on the decline across much of the region and a thriving black market for pot — plus state-sanctioned recreational marijuana sales in Washington and Colorado — the spread of cannabis cultivation is now seen by many environmentalists and government scientists as the greatest threat to forests and streams damaged by decades of heavy human use.

"There's no real question the marijuana industry is now the biggest single sector in terms of our concerns," said Greacen, Friends of the Eel River director.

He said regulating the industry and its water use would go a long way toward fixing the problem.

If growers collected all their water during the rainy season and stored it in permitted tanks or ponds — like many other farmers — marijuana's water consumption would not be such an issue, Greacen said.

Blake, the Emerald Cup founder, agreed. He said most locally based growers are conscientious, both about staying within plant limits and using their own springs or buying tanks of water. But there are others who buy, rent or trespass on water-short properties and then divert water illegally to grow their crops, he said. Law enforcement officials say such growers also tap into neighbors' springs and water tanks.

"It's the big commercial growers that are giving all the people who have been doing a good job up here a bad name," Blake said.

Dale Gieringer, state coordinator of the National Organization for the Reform of Marijuana Laws, a group that advocates for marijuana legalization, said growers are taking too much of the blame for the state's water woes.

"I don't think marijuana is responsible for most of the water problems in California," he said. But, if the marijuana plant counts cited in the study are correct, "that could have an impact" in those watersheds, he acknowledged.

Wildlife officials are quick to say that many local marijuana growers are following the rules.

But there are quite a few who don't.

Fish and Wildlife officials last year investigated 264 marijuana-growing operations in the state and helped remove 129 illegal dams being used to irrigate pot, said Capt. Nathaniel Arnold, who runs the department's statewide marijuana team.

Of those operations, about 70 were in Lake and Mendocino counties, he said.

Agency officials say they are limited in what they can accomplish because they are outnumbered by marijuana-growing offenders.

"We just don't have enough staff" to investigate every complaint, Feiler said.

The cases often take years to investigate and prosecute.

State regulators recently worked on three cases, each involving an unauthorized dam on one tributary to the Navarro River in Comptche, west of Ukiah.

Another case involves a Willits-area property rented to marijuana growers who used bulldozers to clear several acres of forest.

On Friday, the Oakland landowner, Joung Min Yi, reached a settlement with the state that requires him to pay $56,404 in penalties for state and federal water code violations.

He also is required to restore the land, work that has reportedly cost more than $80,000, Feiler said.

Most cases pursued by water regulators are resolved through civil fines rather than criminal charges, in part because it requires fewer resources, he said.

Marijuana growers aren't the only ones taking water without permission. Last year, a Mendocino County vineyard was fined $33,800 for diverting water from an unnamed creek into its irrigation reservoir.

Legislators have proposed stronger environmental protection measures in response to the problem. Pending state legislation would boost funding for water and wildlife investigations connected to illegal marijuana cultivation.

In Mendocino County, Sheriff Allman has initiated a water theft hotline and said cases are being being vigorously prosecuted. The District Attorney's Office does not have statistics available on water prosecutions, spokesman Mike Geniella said.

The Department of Fish and Wildlife has put together a team dedicated to dealing with marijuana, Foy said. Water and wildlife officials also are asking marijuana growers to learn and follow water regulations. The State Water Resources Control Board website has information about obtaining permits to collect and store water.

The permits and requirements apply to any site preparation work, "regardless of crop," the state website notes.

Still, regulators and environmentalists are concerned that the explosion of marijuana in the region, without greater controls, will ruin the landscape for everyone.